In general relativity, the motion of an extended test body is influenced by its proper rotation, or spin. We present a covariant and physically self-consistent Hamiltonian framework to study this motion, up to quadratic order in the body’s spin, including a spin-induced quadrupole, and in an arbitrary background spacetime. The choice of spin supplementary condition and degeneracies associated with

This study derives the mass spectrum and entropy of the Brown–Kuchař dust in anti-de Sitter (AdS) spacetime using the fractional Wheeler–DeWitt (WDW) equation. The generalized fractional WDW equation is formulated using a fractional quantization map, demonstrating a correlation between the fractal mass dimension of the Brown–Kuchař dust and Lévy’s fractional parameter α of the Riesz fractional quantum

The Laser Interferometer Space Antenna (LISA) mission is being developed by ESA with NASA participation. As it has recently passed the Mission Adoption milestone, models of the instruments and noise performance are becoming more detailed, and likewise prototype data analyses must as well. Assumptions such as Gaussianity, stationarity, and data continuity are unrealistic, and must be replaced with physically

Aiming at applications for gravitational wave (GW) detection, in particular at the reduction of quantum back action noise, we propose a novel scheme how to obtain back action evading measurements performed on an opto-mechanical cavity, by introducing a negative radiation pressure coupling between the cavity field and the end mirror. The scheme consists of introducing a double cavity with end mirrors

The McVittie metric does not describe a physical black hole in an expanding Universe because the curvature scalar and pressure at its event horizon are infinite. We show that extending this metric to an inhomogeneous scale factor, which depends on both the time and radial coordinate, removes those infinities by imposing at the horizon the constancy of the Hubble parameter and a particular constraint

We compute the gravitational radiation–reaction (RR) force on a compact binary source at the fourth-and-a-half post-Newtonian (4.5PN) order of general relativity, i.e. 2PN order beyond the leading 2.5PN radiation reaction. The calculation is valid for general orbits in a general frame, but in a particular coordinate system which is an extension of the Burke–Thorne coordinate system at the lowest order

The realization of clock synchronization and syntonization via inter-satellite link is of vital importance for navigation, space-based Very Long Baseline Interferometry (VLBI) experiments and precision tests of fundamental physics. We study the accuracy and stability of time and frequency transfer via inter-satellite link in Cis-lunar space. A relativistic time transfer model using microwave dual one-way

Dibaryons are the simplest system in which the baryon-baryon interaction, and hence the underlying quark-quark interaction, can be studied in a clear way. Although the only dibaryon known today is the deuteron (and possibly the d*), fully heavy dibaryons are good candidates for bound states because in such systems the kinetic energy is small and the high symmetry of the wave function favors binding

The backreaction of quantum degrees of freedom on classical backgrounds is a poorly understood topic in theoretical physics. Most often it is treated within the semiclassical approximation with the help of various prescriptions accounting for the effect of quantum excitations on the dynamics of the background. We focus on two popular ones: (i) the mean-field approximation whereby quantum degrees of

We study high-energy scattering at fixed angle in the planar limit of non-Abelian gauge field theories from type IIB superstring theory scattering amplitudes. First, we consider four-glueball scattering described in terms of the four-dilaton string theory scattering amplitude. We explicitly calculate some angular integrals of four scalar spherical harmonics on the five sphere leading to selection rules

The laser of an intense electromagnetic field provides an important tool to study the strong-field particle physics. The nonlinear Compton scattering was observed in the collision of an ultrarelativistic electron beam with a laser pulse in the 1990s. The precision measurement of the nonlinear Compton scattering shines the light on the studies of strong-field quantum electrodynamics (QED) and nonlinear

Quasinormal modes are excited during the ringdown phase of black holes after merger. Determination of quasinormal modes of rapidly rotating black holes in alternative theories of gravity has remained a challenge for a long time. Here we discuss in detail our recently developed method to extract the quasinormal modes for rapidly rotating black holes in Einstein-Gauss-Bonnet-dilaton theory. We first

In this paper, we present a second realization of the Weyl double copy (WDC) in four-dimensional algebraic type D spacetime. We show that any type D vacuum solution admits an algebraically general Maxwell scalar on the curved background that squares to give the Weyl scalar. The WDC relation defines a scalar field that satisfies the Klein-Gordon equation sourced by the Weyl scalar on the curved background

The main aim of this paper is to simplify and popularise the construction from the 2013 paper by Apostolov, Calderbank and Gauduchon, which (among other things) derives the Plebański–Demiański family of solutions of GR using ideas of complex geometry. The starting point of this construction is the observation that the Euclidean versions of these metrics should have two different commuting complex structures

In this article, we investigate the interactions of a Yang-Mills (YM) wave fluctuation of a classical isotropic, homogeneous YM condensate, which models gluon plasma, with a gravitational wave (GW). We re-analyse the study of fluctuations of the gluon plasma using vector decomposition of the gauge field into scalar, longitudinal, and transverse modes. We find that there is an energy transfer between

The implementation of Fabry–Perot cavities in gravitational-wave detectors has been pivotal to improving their sensitivity, allowing the observation of an increasing number of cosmological events with higher signal-to-noise ratio. Notably, Fabry–Perot cavities play a key role in the frequency-dependent squeezing technique, which provides a reduction of quantum noise over the whole observation frequency

We study the finite temperature and edge induced effects on the charge and current densities for a massive spinor field localized on a 2D conical space threaded by a magnetic flux. The field operator is constrained on a circular boundary, concentric with the cone apex, by the bag boundary condition and by the condition with the opposite sign in front of the term containing the normal to the edge. In

Precession in black-hole binaries is caused by a misalignment between the total spin and the orbital angular momentum. The gravitational-wave emission of such systems is anisotropic, which leads to an asymmetry in the ±m multipoles when decomposed into a spherical harmonic basis. This asymmetric emission can impart a kick to the merger remnant black hole as a consequence of linear momentum conservation

Gravity is derived from an entropic action coupling matter fields with geometry. The fundamental idea is to relate the metric of Lorentzian spacetime to a quantum operator, playing the role of an and to describe the matter fields topologically, according to a Dirac-Kähler formalism, as the direct sum of a 0-form, a 1-form and a 2-form. While the geometry of spacetime is defined by its metric, the matter

The kinematic algebra of Yang-Mills theory can be understood in the framework of homotopy algebras: the L∞ algebra of Yang-Mills theory is the tensor product of the color Lie algebra and a kinematic space that carries a C∞ algebra. There are also hidden structures that generalize Batalin-Vilkovisky algebras, which explain color-kinematics duality and the double copy but are only partially understood

The conformally invariant scalar equation permits the Robin boundary condition at infinity of asymptotically AdS spacetimes. We show how the dynamics of a conformal cubic scalar field on the Reissner-Nordström-anti-de Sitter background depend on the black hole size, charge, and choice of the boundary condition. We study the whole range of admissible charges, including the extremal case. In particular

The ongoing Run 3 at the Large Hadron Collider (LHC) is substantially increasing the luminosity delivered to the experiments during Run 1 and Run 2. The advent of the high-luminosity upgrade of the LHC (Run 4 to 6), as well as the improvements to all detectors, will allow for the collection of an unprecedented amount of data in the next decade. This opens the possibility of performing measurements

We study the zero-dimensional prototype of the path integrals in quantum mechanics and quantum field theory, with the action S(ϕ)=σ2ϕ2+λ4ϕ4. Using the Lefschetz thimble decomposition and the saddle point expansion, we derive multiple asymptotic formal series of the correlation function associated with the perturbative and nonperturbative saddle points. Furthermore, we reconstruct the exact correlation

We investigate the thermodynamics of Reissner-Nordström Gauss-Bonnet (RN-GB) black holes in anti–de Sitter (AdS) space with three horizon geometries (k=+1,0,−1) within the grand canonical ensemble. Using the recently developed topological approach to black hole thermodynamics, inspired by Duan’s ϕ-mapping theory, we analyze the black holes by treating both critical points in the phase diagram and black

In this paper, we consider the time evolution of entanglement asymmetry of the black hole radiation in the Hayden-Preskill thought experiment. We assume the black hole is initially in a mixed state since it is entangled with the early radiation. Alice throws a diary maximally entangled with a reference system into the black hole. After the black hole has absorbed the diary, Bob tries to recover the

Recent proposals suggested quantum clock interferometry for tests of the Einstein equivalence principle. However, atom interferometric models often include relativistic effects only in an fashion. Here, instead, we start from the multiparticle nature of quantum-delocalizable atoms in curved spacetime and generalize the special-relativistic center of mass (c.m.) and relative coordinates that have previously

The effect of noise induced by gravitons on a Bose-Einstein condensate has been explored in Sen and Gangopadhyay [Probing the quantum nature of gravity using a Bose-Einstein condensate, ]. In the previous paper, we investigated the effects of graviton while detecting a gravitational wave using a Bose-Einstein condensate. In this work, we shall explicitly calculate the decoherence due to the noise of

The role of asymmetric nuclear medium on the properties of kaon is investigated at zero and finite temperature employing a hybrid approach integrating the light cone quark model and the chiral SU(3) quark mean field model. The in-medium quark masses are calculated within the chiral SU(3) quark mean field model and are used as inputs to study the medium modifications in the kaon properties. In particular

In this paper, we revisit and extend the analysis of the no-boundary wave function for the minisuperspace model in which the universe is described by a biaxial Bianchi IX metric. As matter content, we simply assume a positive cosmological constant. We find that two Stokes phenomena occur, at large squashing parameters of the spatial section of the Universe. These Stokes phenomena eliminate potentially

By employing the perturbiner method, we study the tree- and one-loop-level amplitudes in (anti)self-dual Yang-Mills, focusing on color-kinematics duality and double copy features; they arise naturally even in the fully off-shell case. In particular, we calculate the respective the Kawai-Lewellen-Tye relations for tree-level Berends-Giele currents and color-kinematics master numerators at one loop,

Important aspects of quantum chromodynamics (QCD) factorization theorems are the properties of the objects involved that can be identified as universal. One example is that the definitions of parton densities and fragmentation functions for different types of hadrons differ only in the identity of the nonperturbative states that form the matrix elements, but are otherwise the same. This leads to independence

The generalization of photon spheres by considering the trajectories of massive particles leads to the definition of massive particle surfaces (MPS). These surfaces, built with the trajectories of massive particles, have a partial umbilicity property. Using the geodesic and Gaussian curvature of the Jacobi metric (a Riemannian metric), we derive a general condition for the existence of a massive particle

The final stage of black hole evaporation is a potent probe of physics beyond the Standard Model: Hawking-Bekenstein radiation may be affected by quantum gravity “memory burden effects,” or by the presence of “dark,” beyond-the-Standard-Model degrees of freedom in ways that are testable with high-energy gamma-ray observations. We argue that information on either scenario can best be inferred from measurements

We propose a microscopic definition of finite cutoff JT quantum gravity on the disk, both in the discretized and in the continuum points of view. The discretized formulation involves a new model of so-called self-overlapping random polygons. The measure is not uniform, implying that the degrees of freedom are not in one-to-one correspondence with the shape of the boundary. The continuum formulation

Probing quantumness in curved spacetime is regarded as one of the fundamental and important topics in the framework of relativistic quantum information. In this work, we focus on the theoretical feasibility of probing quantum properties in de Sitter (dS) and anti–de Sitter (AdS) spacetimes via detectors. By employing the Unruh-DeWitt detector coupled with a massless scalar field, which is treated as

We investigate the influence of a phase transition from hadronic matter to a deconfined quark phase inside a neutron star on its cooling behavior including the appearance of twin star solutions in the mass-radius diagram. We find that while the inferred neutrino luminosity of cold transiently accreting star in MXB 1659-29 is reproduced in all of the constructed twin star models, the luminosity of a

The adage that ideas are cheap in astronomy, with execution being paramount, may already be obsolete. The impact of large language models (LLMs) on research looms on the horizon, compelling the astronomy community to reevaluate the very metrics of merit, the definition of research identity and methodology, and the foundations of education.

Artificial intelligence (AI) is everywhere — from billion-dollar investments in companies like Anthropic, to chatbot romances, and even conservationists using it to save the red squirrel. In science, its applications are undeniable, but what happens when we try to use AI to tackle the very technical art of scientific writing? My colleagues and I recently gathered at the Kavli Institute for Theoretical

In this paper we give an extensive description of Weyl quadratic gravity as the gauge theory of the Weyl group. The previously discovered (vectorial) torsion/non-metricity equivalence is shown to be built-in as it corresponds to a redefinition of the generators of the Weyl group. We present a generalisation of the torsion/non-metricity duality which includes, aside from the vector, also a traceless

Some calculations of parton distributions from first principles only give access to a limited range of Fourier modes of the function to reconstruct. We present a physically motivated procedure to regularize the inverse integral problem using a Gaussian process as a Bayesian prior. We propose to fix the hyperparameters of the prior in a meaningful physical fashion, offering a simple implementation,

Leptophilic axionlike particles (ALPs) exhibit rich phenomenology, focusing exclusively on interactions between an ALP and Standard Model leptons. Through integration by parts, it is shown that both the three-point interaction, aℓ¯ℓ, and the four-point interaction, aℓ−νW+, play significant roles, making the flavor portal particularly compelling. For ALPs with masses ranging from O(1) MeV to O(1) GeV

A novel approach for estimating the lower end of the SU(3) conformal window is presented through the study of center vortex geometry and its dependence on the number of fermion flavors Nf. Values ranging from Nf=2–8 are utilized to infer an upper limit for vortex behavior in the low Nf phase, which may inform the transition to the conformal window. The simulations are performed at a single lattice

The string landscape statistical draw to large scalar soft masses leads to a mixed quasidegeneracy/decoupling solution to the supersymmetry (SUSY) flavor and CP problems where first/second generation matter scalars lie in the 20–40 TeV range. With increasing first/second generation scalars, SUSY models actually become more natural due to two-loop renormalization group (RG) effects that suppress the

B meson rare decays play a crucial role in exploring new physics beyond the standard model. In this study, we explore the rare decay process Bs0→μ+μ− in a flavor violating extension of the Minimal Supersymmetric Standard Model (MSSM), namely, the μ-from-ν SSM (μνSSM). Combined with the decay B¯→Xsγ, the numerical results indicate that the μνSSM can successfully accommodate the experimental data for

We propose a new realization of light Dirac neutrino mass and dark matter (DM) within the framework of a non-Abelian discrete flavor symmetry based on A4 group. In addition to A4, we also consider a Z2 and an unbroken global lepton number symmetry U(1)L to keep unwanted terms away while guaranteeing the Dirac nature of light neutrinos. The field content, their transformations, and flavon vacuum alignments

With the advent of advanced machine learning techniques, boosted object tagging has witnessed significant progress. In this article, we take this field further by introducing novel architectural modifications compatible with a wide array of GNN architectures. Our approach advocates for integrating capsule layers, replacing the conventional decoding blocks in standard GNNs. These capsules are a group

The simplified connection between Standard Model (SM) particles and light dark matter (LDM) can be introduced via spin-0 and spin-1 lepton-specific mediators. Moreover, in a mediator mass range from sub-MeV to sub-GeV, fixed-target facilities such as NA64e, LDMX, NA64μ, and M3 can potentially probe such particles of the hidden sector via missing energy signatures that are described by the bremsstrahlunglike

In this paper, we present a comprehensive toolbox for studying Carrollian stretched horizons, encompassing their geometry, dynamics, symplectic geometry, symmetries, and corresponding Noether charges. We introduce a precise definition of ruled stretched Carrollian structures (sCarrollian structures) on any surface, generalizing the conventional Carrollian structures of null surfaces, along with the

We discuss the information loss issue for completely evaporating black holes in the context of a globally hyperbolic spacetime that maintains unchanged the entire semiclassical picture except for the ‘last evaporation breath,’ which pertains to full quantum gravity. Even though observers outside the black hole cannot access information that enters the horizon, there is no actual loss of information

A long-term cooling trend through the Ordovician Period, from 487 to 443 Ma, is recorded by oxygen isotope data. Tropical ocean basins in the Early Ordovician were hot, which led to low oxygen concentrations in the surface ocean due to the temperature dependence of oxygen solubility. Elevated temperatures also increased metabolic demands such that hot shallow water environments had limited animal diversity

To improve the theoretical understanding of multiquark states like Zb(10610) and Zb(10650), we calculate the heavy-meson heavy-(anti)meson scattering potential up to next-to-leading order, O(Q2), within chiral effective field theory (χEFT) employing a power counting scheme that explicitly keeps track with the large momentum scale Q∼2μδ (where δ=mV−mP is the vector-pseudoscalar mass difference and μ

We conduct the first comprehensive P-wave four-body dynamical calculations of the fully charmed tetraquark systems within the quark potential model. We apply the Gaussian expansion method to solve the four-body Schrödinger equation, incorporating both dimeson and diquark-antidiquark spatial configurations. The matrix elements of P-wave states are calculated analytically using the infinitesimally shifted

We carry out a comprehensive analysis of the Landau-Khalatnikov-Fradkin transformations for a charged fermion propagator at the two-loop level in quantum electrodynamics (QED). Starting with an arbitrary covariant gauge ξ and space-time dimension d, we provide its explicit expressions in three- and four-dimensional QED. We begin with the tree-level fermion propagator in the Landau gauge and gauge-transform

We revisit the notion of nuclear parton-to-pion fragmentation functions at next-to-leading order accuracy as an effective description of hadroproduction in nuclear environments such as in semi-inclusive lepton-nucleus deep-inelastic scattering and in single inclusive proton-nucleus collisions. We assess their viability in the face of very precise data collected for the latter at the CERN-LHC over the

The MiniBooNE low-energy excess stands as an unexplained anomaly in short-baseline neutrino oscillation experiments. It has been shown that it can be explained in the context of dark sector models. Here, we provide an overview of the possible new-physics solutions based on electron, photon, and dilepton final states. We systematically discuss the various production mechanisms for dark particles in

We argue that dielectric haloscopes like MADMAX, originally designed for detecting axion dark matter, are also very promising gravitational wave detectors. Operated in resonant mode at frequencies around O(10GHz), these detectors benefit from enhanced gravitational wave to photon conversion at the surfaces of a stack of thin dielectric disks. Since the gravitational wave is relativistic, there is an